Exam 1 - Week 3 - Dysrhythmias

Question 1

When do you choose rate control?

Answer 1

Class 2 & 4
Use AV nodal agents
Asymptomatic
Without CHF

Question 2

When do you choose rhythm control?

Answer 2

Class 1 & 3
Interfering cellular level, interfering electrical/pharm
symptomatic, with CHF

Question 3

What is class 1?

Answer 3

Na channel blockers

Question 4

What is class 1a?

Answer 4

quinidine, procainimide, disopyramide

Older meds, rarely used

Question 5

What rhythms are class 1a drugs used for?

Answer 5

ventricular arrythmias, recurrent afib, WPW syndrome

Question 6

What is class 1b?

Answer 6

lidocaine, phenytoin, Mexiletine

Question 7

What rhythms are class 1b drugs used for?

Answer 7

MI (discouraged now)
Cause asystole, vtach, and afib
Used by specialist only

Question 8

What is class 1c?

Answer 8

flecainide, propafenone

Question 9

What is class 1c used for?

Answer 9

Doesn’t affect action potention (no shift)

Prevents paroxysmal afib, tx of recurrent tachy, contraindicated post MI

Question 10

What labs do you want with class 1c?

Answer 10

LFTs, CBC, ANA, kidney fx, urine pH (affects drug excretion)

Question 11

What diagnostic test do you want with class 1c?

Answer 11

EKG–look at QRS

Should see 10% increase to know drug is effective

Question 12

Special considerations for admin of class 1c?

Answer 12

Use with AV nodal agents (BB and CCB)

Without use of AV nodal agent you can contribute to ventricular rhythm which can be fatal

Question 13

What are class 2 drugs?

Answer 13

Beta-Blockers

Question 14

How do class 2 drugs work?

Answer 14

Decrease conduction through AV node and block catecholamine response

Question 15

What do class 2 drugs treat?

Answer 15

SVT (atrial tachy)

Question 16

Name four class 2 drugs.

Answer 16

Atenolol
Metoprolol (tartrate & succinate)
Nadolol
Propranolol

Question 17

What do class 2 drugs do?

Answer 17

Control rate and rhythm

Question 18

Can class 2 drugs be used alone?

Answer 18

Effective as monotherapy

Question 19

What are class 3 drugs?

Answer 19

K+ channel blockers

Question 20

What is the MOA of class 3 drugs?

Answer 20

Block K+prolong repolarization

Question 21

What is different about the class 3 drug sotalol?

Answer 21

It is a beta blocker and does not convert

Question 22

Name four class 3 drugs

Answer 22

Amiodarone, sotalol, dofetilide, drondedarone

Question 23

What is significant about class 3 drugs?

Answer 23

Pt needs to stay in hospital to observe for side effects before discharge

Question 24

What are special considerations for dofetilide?

Answer 24

If you miss a dose, do NOT double, take next dose.

If you miss a dose again, go to the hospital to start over. Compliance is important.

Question 25

What is significant about drondedarone?

Answer 25

BLACK BOX WARNING--contraindicated in NYHA stages II-IV. | Contributes to HF and death in stage 2 & 3

Question 26

What is significant about amiodarone?

Answer 26

Best drug for afib. | Can turn patient's skin blue

Question 27

What labs do you monitor with amiodarone?

Answer 27

TSH, LFT, BMP (can damage, lungs, liver & thyroid)

Question 28

What are class 4 drugs?

Answer 28

Calcium Channel Blockers

Question 29

What is MOA for class 4 drugs

Answer 29

Decrease conduction through AV node -shorten Phase 2-plateau- (shorten Action Potential) Allow adrenergic control of HRT and contractility

Question 30

Why is class 4 questionable in HF?

Answer 30

Decreases contractility of heart

Question 31

What are nondihydropyridines?

Answer 31

Older class, more antianginal properties, minimal effect on BP, negative inotropic effect, constipation Verapamil and diltiazem

Question 32

Special considerations for diltiazem?

Answer 32

Not as many AE as BB Good negative inotropic effect Can cause constipation in elderly

Question 33

What drugs are in class 5?

Answer 33

Digoxin, mag sulfate, adenosine

Question 34

Digoxin

Answer 34

Decreases conduction through AV node Increases Vagal activity Action is central-on CNS

Question 35

Adenosine

Answer 35

Resets heart, 2 doses of 6mg | ED to convert SVT, AVRT, AVNRT

Question 36

Mag Sulfate

Answer 36

Torsades de pointes